Now that states have a complete set of members, the linked list of

shifts is useless: just fill directly the state's shifts member.
* src/state.h (shifts): Remove the `next' member.
* src/LR0.c (first_state, last_state): Remove.
Adjust the callers.
(augment_automaton): Don't look for the shifts that must be added
a shift on EOF: it is those of the state we looked for!  But now,
since shifts are attached, it is no longer needed to looking
merely by its id: its number.

diff --git a/ChangeLog b/ChangeLog
index 34ac5ff858aa4b2463ae537a5406337f25d38eba..1df9c0a26582fc998cff4881e429097f52bc27a6 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,17 @@
+2001-12-10  Akim Demaille  <akim@epita.fr>
+
+       Now that states have a complete set of members, the linked list of
+       shifts is useless: just fill directly the state's shifts member.
+
+       * src/state.h (shifts): Remove the `next' member.
+       * src/LR0.c (first_state, last_state): Remove.
+       Adjust the callers.
+       (augment_automaton): Don't look for the shifts that must be added
+       a shift on EOF: it is those of the state we looked for!  But now,
+       since shifts are attached, it is no longer needed to looking
+       merely by its id: its number.
+
+       
 2001-12-10  Akim Demaille  <akim@epita.fr>
 
        * src/LR0.c (augment_automaton): Better variable locality.

diff --git a/src/LR0.c b/src/LR0.c
index 4beca5bef9c1bac16eb75685e771c726169bb0b4..4ea292a9cf03e48286103ce729f9d5d15dfde93c 100644 (file)
--- a/src/LR0.c
+++ b/src/LR0.c
@@ -36,11 +36,9 @@
 int nstates;
 int final_state;
 static state_t *first_state = NULL;
-static shifts *first_shift = NULL;
 
 static state_t *this_state = NULL;
 static state_t *last_state = NULL;
-static shifts *last_shift = NULL;
 
 static int nshifts;
 static short *shift_symbol = NULL;
@@ -322,12 +320,6 @@ save_shifts (void)
   p->number = this_state->number;
   shortcpy (p->shifts, shiftset, nshifts);
   this_state->shifts = p;
-
-  if (last_shift)
-    last_shift->next = p;
-  else
-    first_shift = p;
-  last_shift = p;
 }
 
 
@@ -364,9 +356,6 @@ insert_start_shifting_state (void)
   statep->shifts = sp;
   sp->number = nstates++;
   sp->shifts[0] = nstates;
-
-  last_shift->next = sp;
-  last_shift = sp;
 }
 
 
@@ -396,9 +385,6 @@ insert_eof_shifting_state (void)
   statep->shifts = sp;
   sp->number = nstates++;
   sp->shifts[0] = nstates;
-
-  last_shift->next = sp;
-  last_shift = sp;
 }
 
 
@@ -446,10 +432,6 @@ augment_automaton (void)
       first_state->shifts = sp;
       sp->shifts[0] = nstates;
 
-      /* Initialize the chain of shifts with sp.  */
-      first_shift = sp;
-      last_shift = sp;
-
       /* Create the next-to-final state, with shift to
          what will be the final state.  */
       insert_start_shifting_state ();
@@ -473,29 +455,16 @@ augment_automaton (void)
             the final state.  */
          int i;
 
-         /* Find the shift that leads to this STATEP. */
-         shifts *sp = first_state->shifts;
-         shifts *sp1 = NULL;
-         shifts *sp2 = NULL;
-         while (sp->number < statep->number)
-           {
-             sp1 = sp;
-             sp = sp->next;
-           }
+         /* Find the shift of the inital state that leads to STATEP.  */
+         shifts *sp = statep->shifts;
 
-         sp2 = shifts_new (sp->nshifts + 1);
-         sp2->number = statep->number;
-         statep->shifts = sp2;
-         sp2->shifts[0] = nstates;
+         shifts *sp1 = shifts_new (sp->nshifts + 1);
+         sp1->number = statep->number;
+         statep->shifts = sp1;
+         sp1->shifts[0] = nstates;
          for (i = sp->nshifts; i > 0; i--)
-           sp2->shifts[i] = sp->shifts[i - 1];
-
-         /* Patch sp2 into the chain of shifts in place of sp,
-            following sp1.  */
-         sp2->next = sp->next;
-         sp1->next = sp2;
-         if (sp == last_shift)
-           last_shift = sp2;
+           sp1->shifts[i] = sp->shifts[i - 1];
+
          XFREE (sp);
 
          insert_eof_shifting_state ();
@@ -505,31 +474,23 @@ augment_automaton (void)
          /* There is no state for `start: start . ...'. */
          int i, k;
          shifts *sp = first_state->shifts;
-         shifts *sp2 = NULL;
+         shifts *sp1 = NULL;
 
-         /* There is no next-to-final state as yet.  */
-         /* Add one more shift in first_shift,
-            going to the next-to-final state (yet to be made).  */
-         sp2 = shifts_new (sp->nshifts + 1);
-         first_state->shifts = sp2;
+         /* Add one more shift to the initial state, going to the
+            next-to-final state (yet to be made).  */
+         sp1 = shifts_new (sp->nshifts + 1);
+         first_state->shifts = sp1;
          /* Stick this shift into the vector at the proper place.  */
          statep = first_state->next;
          for (k = 0, i = 0; i < sp->nshifts; k++, i++)
            {
              if (statep->accessing_symbol > start_symbol && i == k)
-               sp2->shifts[k++] = nstates;
-             sp2->shifts[k] = sp->shifts[i];
+               sp1->shifts[k++] = nstates;
+             sp1->shifts[k] = sp->shifts[i];
              statep = statep->next;
            }
          if (i == k)
-           sp2->shifts[k++] = nstates;
-
-         /* Patch sp2 into the chain of shifts
-            in place of sp, at the beginning.  */
-         sp2->next = sp->next;
-         first_shift = sp2;
-         if (last_shift == sp)
-           last_shift = sp2;
+           sp1->shifts[k++] = nstates;
 
          XFREE (sp);
 

diff --git a/src/state.h b/src/state.h
index d505565ac8d83c72131b11f923c5c97c484b6b3f..f7244b4b17cd11d8f6805ba8ceb3eda1c4f7d93a 100644 (file)
--- a/src/state.h
+++ b/src/state.h
@@ -95,7 +95,6 @@
 
 typedef struct shifts
 {
-  struct shifts *next;
   short number;
   short nshifts;
   short shifts[1];